Exactly 100 years ago, U.S. President Woodrow Wilson created the National Park Service. The goal was "to conserve the scenery and the natural and historic objects and the wild life therein and to provide for the enjoyment of the same." Today, the National Park system maintains 412 places all over the country, covering more than 34 million hectares of land. These areas include national parks, monuments, battlefields, military parks, historical parks, historic sites, lakeshores, seashores, recreation areas, scenic rivers and trails, and the White House. Over 300 million people visited national parkland last year. The oldest national park in the country, established in 1872 (even before the NPS existed) is Yellowstone, an 800,000 hectare woodland that sits on top of an ancient caldera. It features hot water geysers, stunning pools of volcanically heated water, and a greatest hits of American wildlife. Theodore Roosevelt, known as 'the conservation president,' protected many other unique sites during his administration (1901-1909), parklands, forests and monuments. The newest park, established in 2013, is the Pinnacles in California, ancient spires of rock that are the remnants of an ancient volcano. Celebration Held on National Mall The Park Service threw a party for itself on the National Mall in Washington, D.C. Thursday to celebrate the anniversary. The party took place in one of the most visited places in the park system, the three-kilometer stretch of land between the U.S. Capitol and the Lincoln Memorial that hosts about 24 million visitors per year. It is anchored in the middle by the obelisk known as the Washington Monument. Thursday's festivities on the Mall include "Rangerpalooza," an exhibit featuring information on the men and women who work in the national parks; a kids' scavenger hunt, and an evening concert and beer garden. Earlier Thursday, hundreds of volunteers gathered on the Mall, armed with brown, green and white umbrellas to form the National Parks logo for an aerial photograph. And a naturalization ceremony was held at the World War II Memorial, one of the newest memorials on the Mall. National parks across the United States offered free admission Thursday, along with locally produced celebrations such as refreshments, visits with park rangers and other special activities. To learn more about the National Park Service and the hundreds of sites it oversees, visit www.nps.gov.